rfkill: copy the name into the rfkill struct

Some users of rfkill, like NFC and cfg80211, use a dynamic name when
allocating rfkill, in those cases dev_name(). Therefore, the pointer
passed to rfkill_alloc() might not be valid forever, I specifically
found the case that the rfkill name was quite obviously an invalid
pointer (or at least garbage) when the wiphy had been renamed.

Fix this by making a copy of the rfkill name in rfkill_alloc().

Cc: stable@vger.kernel.org
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

diff --git a/net/rfkill/core.c b/net/rfkill/core.c
index b41e9ea2ffff461847465d621a3284480f433cc5..f53bf3b6558b094b6e1b379568620157b4ffae17 100644 (file)
--- a/net/rfkill/core.c
+++ b/net/rfkill/core.c
@@ -49,7 +49,6 @@
 struct rfkill {
        spinlock_t              lock;
 
-       const char              *name;
        enum rfkill_type        type;
 
        unsigned long           state;
@@ -73,6 +72,7 @@ struct rfkill {
        struct delayed_work     poll_work;
        struct work_struct      uevent_work;
        struct work_struct      sync_work;
+       char                    name[];
 };
 #define to_rfkill(d)   container_of(d, struct rfkill, dev)
 
@@ -876,14 +876,14 @@ struct rfkill * __must_check rfkill_alloc(const char *name,
        if (WARN_ON(type == RFKILL_TYPE_ALL || type >= NUM_RFKILL_TYPES))
                return NULL;
 
-       rfkill = kzalloc(sizeof(*rfkill), GFP_KERNEL);
+       rfkill = kzalloc(sizeof(*rfkill) + strlen(name) + 1, GFP_KERNEL);
        if (!rfkill)
                return NULL;
 
        spin_lock_init(&rfkill->lock);
        INIT_LIST_HEAD(&rfkill->node);
        rfkill->type = type;
-       rfkill->name = name;
+       strcpy(rfkill->name, name);
        rfkill->ops = ops;
        rfkill->data = ops_data;